Threat of Global Warming
There are two burning questions that I feel need to be answered before exploring the aspects of global warming. They are what is the greenhouse effect and how does the green house effect contribute to global warming? Gases in the atmosphere are transparent to visible light but absorb infrared (heat) waves that are reradiated from the earth’s surface (Cunningham, Cunningham, Saigo 05). However, some greenhouse gases occur naturally in the atmosphere, while others result from human activities. Naturally occurring greenhouse gases include water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Carbon dioxide is released to the atmosphere when solid waste, fossil fuels (oil, natural gas, and coal), wood and wood products are burned. Methane is emitted during the production and transport of coal, natural gas, and oil and the raising of livestock.
The atmosphere, when loosely compared to the glass of a greenhouse, transmits sunlight while trapping heat inside is called the green house effect. The greenhouse effect is a natural atmospheric process that is necessary for life, as we know it. Too strong of a greenhouse effect that is caused by the burning of fossil fuels and deforestation, may cause harmful environmental change. The greenhouse effect is only troublesome when it gets too strong and warms things too much. And that’s just what scientists say has happened over the last 150 years or so as the people of industrialized nations have extracted Earth’s vast buried stores of fossil fuels and burned them.
Each greenhouse gas differs in its ability to absorb heat in the atmosphere. Methane traps over 21 times more heat per molecule than carbon dioxide, and nitrous oxide absorbs 270 times more heat per molecule than carbon dioxide. Scientists know for certain that human activities are changing the composition of Earth’s atmosphere. Increasing levels of greenhouse gases, like carbon dioxide, in the atmosphere since pre-industrial times have been well documented.
Since the start of the Industrial Revolution the atmospheric concentration of carbon dioxide has increased nearly 30 percent, methane has more than doubled, and the nitrous oxide concentration is up about 15 percent. All those extra greenhouse gases mean more and more solar energy is being trapped in the atmosphere, exacerbating the greenhouse effect and making things warmer.
In the simplest terms, global warming is just what it sounds like: the worldwide rise in surface temperatures. The cause of global warming is what’s called the "greenhouse effect." That’s shorthand for the ability of gases in the atmosphere to slow down the release of heat into space at night. Some gases are better at this than others. Carbon dioxide, methane and nitrous oxide are the top three "greenhouse gases." They are very good at absorbing sunlight and converting that energy into heat – rather like a rock does just sitting in the sun.
Since the start of...